Project description:Gene expression from 2 livers and 2 hearts from mouse Mut-ko/ki (MUT p.M700K) described in Forny et al JBC 2016 and 3 livers, 2 hearts from littermate controls
Project description:To analyze the expression profile in the Otx2 knock-in (a knock-in mouse line expressing Otx2 from the Crx locus on chromosome 7) and Crx knockout retina, we performed a microarray analysis using wild-type (Crx +/+), Otx2 KI (Crx Otx2/Otx2) and Crx KO (Crx -/-) retina at P12.
Project description:Antigen Ki-67 is a nuclear protein expressed in proliferating mammalian cells. It is widely used in cancer histopathology but its functions remain unclear. Here, we show that Ki-67 controls heterochromatin organisation. Altering Ki-67 expression levels did not significantly affect cell proliferation in vivo. Ki-67 mutant mice developed normally and cells lacking Ki-67 proliferated efficiently. Conversely, upregulation of Ki-67 expression in differentiated tissues did not inhibit cell cycle arrest. Ki-67 interactors included proteins involved in nucleolar processes and chromatin regulators. Ki-67 depletion disrupted nucleologenesis but did not inhibit pre-rRNA processing. In contrast, it altered gene expression. Ki-67 silencing also had wide-ranging effects on chromatin organisation, disrupting heterochromatin compaction and long-range genomic interactions. Trimethylation of histone H3K9 and H4K20 at heterochromatin was strongly reduced. Overexpression of human or Xenopus Ki-67 induced ectopic heterochromatin formation. Altogether, our results suggest that Ki-67 expression in proliferating cells spatially organises heterochromatin, thereby controlling gene expression.
Project description:PECs from wild-type, NF-IL6KO and KI(LAP) mice were stimulated with or without LPS+IFN-gamma for 12h. We used microarrays to check the difference of gene induction among wild type, KO and KI mice. Keywords: Wild, KO and KI(LAP)
Project description:Methylmalonic acidemias (MMA) consist in a group of autosomal recessive inherited metabolic disorders whose pathogenesis involves the catabolism of propionyl-CoA. The propionyl-CoA produced from the degradation of cholesterol, branched-chain amino acids (valine, isoleucine, methionine, threonine) and the -oxidation of odd-chain fatty acids is converted into methylmalonyl-CoA, which is further converted in succinyl-CoA, required for energy production in the Krebs cycle. In mitochondria of MMA patients, the conversion of methylmalonyl-CoA into succinyl-CoA, catalysed by the vitamin B12-dependent methylmalonyl-CoA mutase (MUT) enzyme, is altered. This can be due to: 1) defective activity of MUT apoenzyme or 2) a defect in the synthesis or transport of adenosylcobalamin (MUT cofactor). In the first case it is referred to as isolated MMA (mut0 or mut- phenotypes if the deficiency is total or partial, respectively), while in the second case as cbl-related MMA (there is a specific disorder according to which gene is mutated) []. The blockage of this enzymatic reaction leads to increase in the levels of methylmalonic acid, hallmark of this group of diseases []. Independently from the pathogenesis, along with methylmalonic acid, other MMA-associated metabolites like acylcarnitines, amino acids and organic acids result altered in MMA [REF]. These metabolites are easily detectable and quantifiable by metabolomics approaches, such as liquid chromatography - tandem mass spectrometry (LC-MS/MS) or gas chromatography - mass spectrometry (GC-MS), in dried blood spots or urine or plasma to make diagnosis. Because of the early onset of MMA in patients, MMA is included in the panel of diseases for the expanded newborn screening in several countries, including Italy [ref]. Our work aims at understanding the mechanisms of cellular damage in MMA disease. The majority of MMA complications arise from brain damage, on which depend neurological alterations and movement disorders. In the brain, the astrocytes are damaged by hyperammonemia, causing edema and hypoperfusion. (REF lavoro) Renal function is commonly compromised in MMA patients, even the pathogenesis of kidney injury is not clear. Renal insufficiency and chronic kidney disease are partially resolved after kidney transplantation. Hyperammonemia and metabolic acidosis are considered as key mechanisms acting in the proximal tubule to lead to renal damage. In fact, general organ metabolic alterations are thought to be caused by the breakdown of branched‐chain amino acids that lead to the accumulation of circulating toxic acidic metabolites. Thus, metabolic acidosis is induced with diminishing of bicarbonate levels. Lactic acidosis and hyperammonemia result as the main metabolic alterations of MMA. (REF lavoro) Results of a previous work on a MUT-knockdown neuroblastoma cell line [Costanzo, 2018] were coherent with the disease, but did not completely elucidate such mechanisms, possibly due to limitation of the cellular model. We presumed that the transient silencing of MUT gene was not sufficient to input long-term decompensation due to absence of this protein. For this reason, we have developed a new cellular model for isolated MMA by stably knocking out MUT gene in HEK293 cell line using CRISPR/CAS9 genome editing technology. We also performed a global proteomic analysis to describe protein changes strictly connected to MUT absence and related altered pathways. Altogether, the results obtained shed new light on the molecular mechanisms of cellular damage, including alterations of cell architecture in combination with the acquisition of a higher sensitivity to stress.
Project description:As TRPC6 channel induces CREB-mediated trancription, Dental pulp cells from TRPC6-mut patient and from 6 controls were analyzed in order to verify if the disruption of TRPC6 leads to transcriptional changes.
Project description:PECs from wild-type, NF-IL6KO and KI(LAP) mice were stimulated with or without LPS+IFN-gamma for 12h. We used microarrays to check the difference of gene induction among wild type, KO and KI mice. Experiment Overall Design: Peritoneal macrophages were collected for RNA extraction and hybridization on Affymetrix microarrays.